[asterisk-bugs] [Asterisk 0016766]: T.38 negotiation fails with Patton SN2400

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16766 
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Reported By:                raivisr
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16766
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           SVN 
JIRA:                       SWP-868 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 244639 
Request Review:              
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Date Submitted:             2010-02-03 16:00 CST
Last Modified:              2010-02-08 10:29 CST
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Summary:                    T.38 negotiation fails with Patton SN2400
Description: 
Patton SN2400 refuses to negotiate T.38 session because of extra newline in
SDP.

[Feb  3 22:31:46] DEBUG[31017] chan_sip.c:    Body  5 [ 22]: m=image 4326
udptl t38
[Feb  3 22:31:46] DEBUG[31017] chan_sip.c:    Body  6 [  0]: 
[Feb  3 22:31:46] DEBUG[31017] chan_sip.c:    Body  7 [ 17]:
a=T38FaxVersion:0

proposed fix:
--- asterisk.orig/channels/chan_sip.c	2010-02-03 23:52:03.000000000 +0200
+++ asterisk/channels/chan_sip.c	2010-02-03 23:58:41.000000000 +0200
@@ -9191,8 +9191,6 @@ static enum sip_result add_sdp(struct si
  		ast_str_append(&m_video, 0, "\r\n");
  	if (needtext)
  		ast_str_append(&m_text, 0, "\r\n");
-	if (add_t38)
-		ast_str_append(&m_modem, 0, "\r\n");
 
  	len = strlen(version) + strlen(subject) + strlen(owner) +
 		strlen(connection) + strlen(session_time);

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---------------------------------------------------------------------- 
 (0117840) lmadsen (administrator) - 2010-02-08 10:29
 https://issues.asterisk.org/view.php?id=16766#c117840 
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Information about where and why the change was added:

lmadsen at asterisk-releaser:~/WORKING/asterisk/trunk/channels$ svn annotate
-r100000:HEAD chan_sip.c | grep "m_modem" | more
184948       file 	struct ast_str *m_modem = ast_str_alloca(256);  /*
Media declaration line for modem */
243860    russell 		ast_str_append(&m_modem, 0, "m=image %d udptl
t38\r\n", ntohs(udptldest.sin_port));
225089       file 			ast_str_append(&m_modem, 0, "c=IN IP4 %s\r\n",
ast_inet_ntoa(udptldest.sin_addr));
184948       file 		ast_str_append(&m_modem, 0, "\r\n");
184948       file 		len += m_modem->used + a_modem->used;
184948       file 		add_line(resp, m_modem->str);
lmadsen at asterisk-releaser:~/WORKING/asterisk/trunk/channels$ svn log
-r184948 http://svn.asterisk.org/svn/asterisk/trunk
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r184948 | file | 2009-03-30 09:37:47 -0500 (Mon, 30 Mar 2009) | 21 lines

Merged revisions 184947 via svnmerge from 
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r184947 | file | 2009-03-30 11:35:47 -0300 (Mon, 30 Mar 2009) | 14
lines
  
  Improve our handling of T38 in the initial INVITE from a device.
  
  We now answer with matching media streams to what is requested. If an
INVITE
  is received with both a T38 and RTP media stream this means we answer
with both.
  For any outgoing calls created as a result of this inbound one no T38 is
requested
  in the initial INVITE. Instead if we start receiving udptl packets we
trigger a
  reinvite on the outbound side.
  
  (closes issue https://issues.asterisk.org/view.php?id=12437)
  Reported by: marsosa
  Tested by: pinga-fogo, okrief, file, afu
  
  Review: http://reviewboard.digium.com/r/208/
........

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Issue History 
Date Modified    Username       Field                    Change               
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2010-02-08 10:29 lmadsen        Note Added: 0117840                          
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